[A rare cause of kidney injury: vitamin D3 intoxication]. / A vesekárosodás ritka oka: D3-vitamin-intoxikáció.

The beneficial effects of vitamin D3 treatment are known, and its side effects are documented. In connection with the case presentation, we would like to sum up the dangers of excessive vitamin D supplementation, and to draw attention to the shortcomings experienced in everyday medical practice. We discuss the tests required to create a diagnosis of vitamin D intoxication, the differential diagnosis, and present the possible treatment strategies. A 57-year-old female patient was admitted to hospital in November 2020 due to complaints of nausea, vomiting, diarrhea and general weakness. Upon admission, laboratory tests confirmed new-onset kidney damage (eGFR 38 mL/min/1.73 m2), calcium metabolism was not checked. During non-invasive investigations, urinary sediment results showed leukocyturia and non-nephrotic proteinuria, but no clear underlying cause was found. Nephrology consultation suggested acute tubular injury, kidney biopsy was performed, immune serology and serum protein electrophoresis tests were ordered. Despite conservative treatment, her kidney function deteriorated further (eGFR 32 mL/d/1.73 m2). The patient arrived at our department in December 2020 with histological results in progress. Laboratory tests taken on arrival confirmed severe hypercalcemia (tCa 3.22 mmol/L, iCa 1.74 mmol/L), and kidney function was stable (eGFR 33 mL/p/1.73 m2). Intact parathyroid hormone level was below the normal range (0.54 pmol/L), 25-OH-vitamin D level was extremely high (1106.2 nmol/L). The patient then admitted that in October 2020, she received a course of "megadose" parenteral vitamin D, but she could not recall the exact dosage nor wanted to mention the department administering the treatment. We diagnosed vitamin D intoxication. Intravenous saline, furosemide and calcitonin treatment was started. The result of the treatment: serum calcium level normalized (2.52 mmol/L), and kidney functions improved (eGFR 54 mL/p/1.73 m2). Vitamin D treatment was stopped. The patients' serum tCa and vitamin D levels normalized by February 2021, and her kidney functions improved (tCa 2.54 mmol/L, 25-OH-vitamin D 125.0 ng/mL, eGFR 72 mL/p/1.73 m2). Kidney biopsy confirmed the presence of acute tubular necrosis. Granulomatous diseases and multiple myeloma were excluded. The symptoms of vitamin D intoxication are non-specific and varied, each case presents a differential diagnostic challenge. Orv Hetil. 2023; 164(47): 1871-1876.

Thyroglobulin level at week 16 of pregnancy is superior to urinary iodine concentration in revealing preconceptual and first trimester iodine supply.

Pregnant women are prone to iodine deficiency due to the increased need for iodine during gestation. Progress has recently occurred in establishing serum thyroglobulin (Tg) as an iodine status biomarker, but there is no accepted reference range for iodine sufficiency during pregnancy. An observational study was conducted in 164 pregnant women. At week 16 of gestation urinary iodine concentration (UIC), serum Tg, and thyroid functions were measured, and information on the type of iodine supplementation and smoking were recorded. The parameters of those who started iodine supplementation (≥150 µg/day) at least 4 weeks before pregnancy (n = 27), who started at the detection of pregnancy (n = 51), and who had no iodine supplementation (n = 74) were compared. Sufficient iodine supply was found in the studied population based on median UIC (162 µg/L). Iodine supplementation ≥150 µg/day resulted in higher median UIC regardless of its duration (nonusers: 130 µg/L vs. prepregnancy iodine starters: 240 µg/L, and pregnancy iodine starters: 205 µg/L, p < .001, and p = .023, respectively). Median Tg value of pregnancy starters was identical to that of nonusers (14.5 vs. 14.6 µg/L), whereas prepregnancy starters had lower median Tg (9.1 µg/L, p = .018). Serum Tg concentration at week 16 of pregnancy showed negative relationship (p = .010) with duration of iodine supplementation and positive relationship (p = .008) with smoking, a known interfering factor of iodine metabolism, by multiple regression analysis. Serum Tg at week 16 of pregnancy may be a promising biomarker of preconceptual and first trimester maternal iodine status, the critical early phase of foetal brain development.

[Novel treatment opportunities in Graves' orbitopathy]. / Új lehetoségek az endokrin orbitopathia kezelésében.

Graves' orbitopathy is the most common extrathyroidal manifestation of Graves' disease. Up to now, curative treatment modalities for the most severe sight-threatening cases have not been developed. Here the authors summarize the treatment protocol of Graves' orbitopathy and review novel therapeutic options. They review the literature on this topic and present their own clinical experience. The authors point out that anti-CD20 antibody could positively influence the clinical course of Graves' orbitopathy. Selenium is efficient in mild cases. Further prospective investigations are warranted.